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I'd hit it
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62 Posts
Discussion Starter #1
Alright...besides me breaking stuff constantly, I have never read a thread about issues with no brake boost because of the supercharger's boost. Granted it's only when RPM is up, but it's pretty damn annoying to me. Anybody elese with blowers notice it? Onyx? Pulling up to a stop sign and decide to california roll it and then change your mind and try to stop right after that little crack of the throttle, then notice you have no brakes. I just purchased the Hydroboost like what's on the diesels...cuz I fucking hate it. :imo Just curious if I am a lone soldier.
 

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HOT AIR BALLOON OWNER
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14,932 Posts
Sounds like low idle vac to me...

What cam you rollin'?
 

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I'd hit it
Joined
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62 Posts
Discussion Starter #3
Hit Man X says:[QUOTE]Sounds like low idle vac to me...

What cam you rollin'?[/QUOTE]

Comp218/224 .563/.568 115

cylinders puched .020, Stage 3 heads. I was on LS1Truck and gave the head valve sizes...2.02 and 1.6 on one of your responses. Max lift on the heads is .6
 

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03 Tahoe
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1,364 Posts
I've never had that.....sounds like a low idle vac to me as well...

Cameron
 

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HOT AIR BALLOON OWNER
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14,932 Posts
Well a 115LSA shouldn't have poor idle vac.

I've never told anyone to run a 2.02" valve on a 4.8/5.3...to me it shrouds the chamber decreasing intake velocity which is not what you want. The max I'd run would be a 1.94" with that small of a bore, stock valve there is 1.89" intake anyway. It's not the power output that effects the valve sizing but the size of the bore and cubic inch total. This is a small motor remember and a 2.02" valve can support a 360-380" motor easily. Hell I've seen lot's of 302/306 5.0's killing on the streets with 1.84-1.9" intake valves on a 4" bore.

A larger valve could help high lift CFM ratings over .450" lift but that would hurt mid lift numbers from .200-.400" I'd think hurting power. Velocity makes power over total air flow.
 
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